In a collaboration between the City University of Hong Kong and Shandong University, both in China, scientists have produced tunable, continuous-wave blue light with a solid-state laser. The results of the study, which appeared in the Sept. 27 issue of Applied Physics Letters, concluded that improvements in the resonator and pump source could lead to the application of the device in spectroscopy, high-density data storage and submarine communications. The research team pumped a 946-nm Nd:YAG laser with a tunable 803- to 814-nm Ti:sapphire laser and intracavity frequency-mixed the emissions using a nonlinear optical crystal of cadmium mercury thiocyanate. The setup produced light from 434.4 to 437.5 nm, with a maximum output of 310 µW.